On 2020/8/17 10:03, Sergey Senozhatsky wrote: > On (20/07/21 13:17), Sergey Senozhatsky wrote: >> Hello, >> >> RFC >> >> We noticed that in a number of cases when we wake_up_process() >> on arm64 guest we end up enqueuing that task on a preempted VCPU. The culprit >> appears to be the fact that arm64 guests are not aware of VCPU preemption >> as such, so when sched picks up an idle VCPU it always assumes that VCPU >> is available: >> >> wake_up_process() >> try_to_wake_up() >> select_task_rq_fair() >> available_idle_cpu() >> vcpu_is_preempted() // return false; >> >> Which is, obviously, not the case. >> >> This RFC patch set adds a simple vcpu_is_preempted() implementation so >> that scheduler can make better decisions when it search for the idle >> (v)CPU. > Hi, > > A gentle ping. > > -ss > _______________________________________________ > kvmarm mailing list > kvmarm@xxxxxxxxxxxxxxxxxxxxx > https://lists.cs.columbia.edu/mailman/listinfo/kvmarm > . Hi Sergey, I have a set of patches similar to yours. https://lore.kernel.org/lkml/20191226135833.1052-1-yezengruan@xxxxxxxxxx/ _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
